U.S. Sen. Ted Cruz, R-Texas, and Democratic challenger Beto O’Rourke are set to square off on the debate stage for the first time Friday evening in Dallas.

The 6 p.m. (5 p.m. Mountain) event at Southern Methodist University is the first of three hourlong debates, and it comes as polls continue to show a tight race between Cruz and O’Rourke, an El Paso congressman. On Friday morning, the Cook Political Report changed its rating of the race from “Lean Republican” to “Toss Up.”

The Dallas debate is being presented by SMU, NBC 5/KXAS and The Dallas Morning News. It will be broadcast live on NBC 5/KXAS, its website and the Dallas Morning News’ website as well. The Texas Tribune will feature the livestream of the debate on this page.

The topic of the debate is domestic policy, and it will be moderated by NBC 5 political reporter Julie Fine and Dallas Morning News political writer Gromer Jeffers. Both candidates will stand at podiums before a 240-person audience.

The next two debates are scheduled for Sept. 30 in Houston and Oct. 16 in San Antonio. Early voting begins Oct. 22.

It was only a week ago that O’Rourke and Cruz had announced an agreement to hold three debates, capping weeks of negotiations between their campaigns.

O’Rourke first challenged Cruz to six debates in May, and while Cruz maintained he was open to debating his opponent, he did not formally respond until July. That is when Cruz proposed five topical debates over three months in five cities.

Among the issues that O’Rourke had with Cruz’s proposed debate schedule was every one fell on a Friday evening during high school football season. That will remain true for the Dallas debate, while the other two debates they ultimately agreed to are set for different days.

Disclosure: Southern Methodist University has been a financial supporter of The Texas Tribune, a nonprofit, nonpartisan news organization that is funded in part by donations from members, foundations and corporate sponsors. Financial supporters play no role in the Tribune’s journalism. Find a complete list of them here.